Base stations that are used in wireless communication systems construct communication areas using cells, which are generally known as macrocells, that have a cell radius of between approximately several kilometers and several tens of kilometers. In these macrocell communication areas, there are cases in which areas having poor communication sensitivity are formed because of shielding objects or because of the geographical situation of the base station or the like. In recent years, heterogeneous networks have become utilized as cell structures that are able to ensure high-speed communication in all communication areas of a macrocell. In heterogeneous networks, base stations for small cells, which are known as microcells, are located in low-sensitivity areas of macrocells. The radius of the communication area of a cell is between approximately several hundred meters and one kilometer.
A method in which a plurality of femtocells (i.e., small cells having a cell radius of approximately several tens of meters) are placed adjacently to each other and are consecutively linked together inside commercial facilities such as shops and restaurants is described, for example, in Patent document 1 (see below) as a technology that employs base stations for small cells. In this technology, handovers of mobile stations between adjacent femtocells is permitted. In this case, wireless transmissions from the base stations of femtocells in which no mobile stations are present are stopped. Consequently, when a mobile station moves into such a femtocell, wireless transmissions from the base station of the femtocell that is adjacent to that femtocell is started.